The present invention relates to the technical field of link elements between parts or elements in general, enabling the assembled-together parts to move angularly, and it relates more particularly to hinges adapted to enable the two united elements to be deployed automatically, and also enabling them to be self-locking in the deployed position.
In the preferred field of application of the invention, namely space applications, it is known that the solar panels of satellites can be hinged by means of hinges that suffer from lack of reliability and from the friction that exists between parts that are in contact. In addition, such hinges are fitted with drive means for the purpose of displacing the solar panels. Hinges of that type, having high levels of friction, require the drive to be overdimensioned in order to obtain a sufficient margin for deploying the panels. When friction is low, then as a consequence, shock at the end of deployment is large. To limit such shock, provision is made for a hinge to be associated with a system for regulating speed, and that leads to implementing a hinge that is relatively complex.
In an attempt to remedy those drawbacks, U.S. Pat. No. 3,386,128 and French patent FR 2 635 077 have proposed connecting together the two hinged elements by means of a plurality of resilient blades of circularly arcuate section, each blade being fixed at respective ends to the two hinged elements. Each hinge strap made in that way, also known as a Carpenter strap, is designed to be folded so as to apply a driving torque between the united elements that tends to deploy them automatically. When the resilient blades are in the deployed position, they exert a locking force between the hinged-together elements. That provides a hinge which is both self-driving and self-locking.
Nevertheless, it turns out that hinges of that type suffer from a first drawback relating to lack of control over the locking of the elements in the deployed position. When the hinge strap reaches its deployed position, and since the opening speed is not zero, it can happen that either the equilibrium position is overshot causing unlocking to take place, or else that a rebound movement occurs causing the hinge to reclose.
Such a hinge suffers from another drawback which is that shocks appear when the hinge locks. During such locking, residual kinetic energy causes the hinge to oscillate about its equilibrium position. The linked-together pieces are therefore subjected to forces of magnitude that increase with increasing amounts of residual kinetic energy. Such stresses lead to the link elements being overdimensioned.
The object of the invention is thus to remedy the drawbacks specified above by proposing a hinge strap that is designed to unite two elements in the general sense, and to provide self-drive and self-locking functions, with the hinge strap being designed so as to control the locking of the elements in the deployed position so that during locking of the hinge, shocks are reduced or even eliminated.
To achieve this object, the invention seeks to provide a self-driving, self-locking hinge strap that presents damping ability.
In accordance with the invention, the hinge strap of the invention is designed to be mounted between two adjacent elements, and is of the type constituted by at least one resilient strip preformed to be of circularly arcuate section and designed to be secured via its two ends to the two elements, and to occupy a folded position and a deployed position.
In accordance with the invention, each resilient strip is provided with a layer of viscoelastic material interposed between one of the faces of the resilient strip and a stress plate so as to obtain a hinge that also provides a damping function.
The invention also seeks to provide a hinge comprising an assembly of hinge straps of the invention. In a preferred embodiment, the hinge comprises first and second assemblies each made up of three hinge straps distributed in two planes.
Various other characteristics appear from the following description given with reference to the accompanying drawings which show, by way of non-limiting examples, embodiments and implementations of the invention.